Activation of the renin-angiotension system has been associated with an increased risk of myocardial infarction. Conversely, ACE inhibition may decrease the frequency of schemic events. This study explores the mechanism through wich activation of the renin-angiostension system may increase the risk of thrombotic events like myocardial infarction. We have started to recruit subjects for the study with good success, we will continue this goal.